Problem: Express this product in scientific notation: $(1.20\times 10^{2})\times (9.00\times 10^{-5})$
Solution: Start by collecting like terms together. $= (1.20\times 9.00) \times (10^{2}\times 10^{-5})$ When multiplying exponents with the same base, add the powers together. $= 10.8 \times 10^{2\,+\,-5}$ $= 10.8 \times 10^{-3}$ To write the answer correctly in scientific notation, the first number needs to be between $1$ and $10$ . In this case, we need to move the decimal one position to the left without changing the value of our answer. $ $ We can use the fact that $10.8$ is the same as $1.080 \times 10$ $ = {1.080 \times 10} \times 10^{-3} $ $= 1.080\times 10^{-2}$